1. Field of the Invention
This invention relates in general to the construction of the drive mechanism for spool winding frames and in particular to a new and useful device for controlling thread spooling drives in which a bobbin package is driven by frictional engagement with a drive roller and wherein the bobbin carrier is rotatably supported on a carrier roller shaft connectable through a double cone clutch acting on conical portion of the bobbin carrier and a conical portion of the carrier roller shaft to interconnect the two for controlled rotation thereof.
2. Description of the Prior Art
Synthetic filaments are generally wound up by frictional roller drives. That is, the bobbin or the bobbin package is driven by applying the drive roller which is rotated at a constant speed against the package. As the bobbin is brought into contact with the drive roller, the bobbin is accelerated to the required circumferential velocity through the tube contacting surfaces and under the effect of appropriately adjusted contacting pressure. Upon attaining the circumferential velocity, the spooling power is transmitted from the drive roller to the surface of the bobbin package. By such an arrangement the bobbin as well as the package is disadvantageously stressed, not the least because of the unavoidable slip of the bobbin or the package relative to the drive roller.
In order to avoid this drawback it is known to provide a device for controlling such thread spooling drive to the effect of obtaining constant wind up velocity. In such a device a speed control D.C. motor is used for driving the bobbin. In addition for controlling the speed of the motor changing with the increasing package, a control roller permanently applying against the package surface is provided. An external rotor of a D.C. synchronous motor serves as the control roller. The rotor receives its circumferential speed corresponding to the desired spooling velocity from a D.C. synchronous generator supplying the motor. Because of the rotary mounting of the stator shaft, a relative rotary motion is produced between the shaft and the control roller. Upon occurrence of a transmission torque between the surfaces of the bobbin and the control roller, the relative rotary motion serves simultaneously as the control variable for the motor. Although the arrangement in accordance with this construction has proved very satisfactory in many respects, the proportion of the mechanical and electrical expensed to the obtained controlling effect of the device is relatively unfavorable.
Another device for controlling the starting velocity of a bobbin carrier which is equipped with a turbine drive includes an arrangement in which the rotatably mounted bobbin carrier shaft carries a turbine wheel with appropriately oriented guide vanes as well as the bobbin tube. The bobbin tube or the thread package which is formed on the tube is in permanent contact with a pilot roller rotating at a constant speed. At the start of the device the turbine wheel is exposed to the compressed air stream L.sub.1, for example of 8 bars which is subsequently reduced at the end of the starting phase to a compressed air stream for example of 4 bars for a supporting blow. Even though this solution involves for example the advantage of a turbine which is relatively elastic from the point of view of the control technique, the realization of such a design requires very considerble expensed if the necessary precision of the manufacture of the turbine wheel or the cost of the air compression are considered.